<div class="videoplay" id="videoplay"> <i class="closeb" onclick="document.getElementById('videoplay').style.display='none';"></i>
  <video class="video_id" id="video_id" controls autoplay ></video>
  <input id="v_file" type="file" style="display:none;" onChange="play()"/>
  <button id="play" onClick="yincang()" class="playbtn">打开MP4视频文件</button>
  <script>
function yincang(){
var v_file=document.getElementById('v_file');
v_file.click();
}
function play(){
var file = document.getElementById('v_file').files[0];
var url = URL.createObjectURL(file);
console.log(url);
document.getElementById("video_id").src = url;

}
</script> 
</div>